Interior Vs. Exterior Paint

A friend of mine started to do remodeling and wanted to paint the house. They were not sure if they were using the right paint. I realized that this is something many people might want to know, so I wrote about it.

In a nutshell:

Exterior paint is made to survive the weather and not get mold, mildew, or fade. Interior paint also resists stains, but it can be scrubbed clean without being damaged. The chemicals in interior paint are also safer for you to breathe.

The difference between Interior and Exterior Paint

As we all know that paints are essential items for homes, commercial buildings as well as other areas of our lives. They are used for different purposes such as decorating a wall, making something more colorful, protecting the surface from natural elements and much more.

However, there is always confusion among many people on whether they can be used inside and outside the home? Is there any major difference between these two types of paint? Which one is better to use in certain areas? The following paragraphs will answer all these questions by providing you with answers about the differences between interior and exterior paints.

Interior Paint

Interior paint is specially formulated for use on interior walls and ceilings. It has a mildew resistant low-odor formula designed to reduce the amount of toxins inside your home. Interior paints are more expensive than exterior paints because they contain better quality pigments, additives and resins which lead to their resistance against wear and fading. They also have anti-mold agents, mildew inhibitors, fungicides and germicides which make them ideal for areas where there is increased humidity or moisture such as bathrooms, kitchens, basements or closets.

Before you choose an interior paint color consider; will it complement other colors in the room? Do you like brighter colors or neutral tones? What kind of lighting do you have? Will it reflect off a light-colored wall and give you a headache? What is your budget?

Interior Paint Buying Guide

  1. Before you purchase any interior paint, make sure that the primer and topcoat of the product are compatible with each other. Some companies sell separate products which need to be used together. Always read instructions carefully before starting work.
  2. Choose your paint colors wisely as they can change the entire look of a room and thus it is very important to choose one that will complement existing furniture and dŽcor or works well in combination with all other elements in the room such as walls, flooring etc. There are thousands of wall paints available today so do browse around for samples of different colors until you find something suitable that will enhance your home’s decor and appeal to your tastes without any regrets.
  3. Prices of interior paints vary and if you need a high quality paint, be ready to pay extra amount. It is always good to check the brand so that you will not make any mistake while purchasing from a reputed company as such reliable brands use only the best paints in their products and are also easier to clean and maintain than low-quality ones. If there’s an option, choose environmentally friendly paints as they do not contain any harmful chemicals which can affect our health when inhaled or touched. Painting experts recommend latex based paint because it is easy to apply, provides long lasting results along with being ecofriendly but it needs proper surface preparation prior to painting otherwise chances are cracks might develop easily on old walls due to correct paint application or wash and wear won’t be the same after a few months.

Exterior Paint

Exterior paint is formulated to be used on the exterior of your home, including outside walls, roofs and fences. Exterior paints are more durable than interior paints because they have higher solids content which helps resist wear and fading from UV rays as well as increased resistance to harsh weather conditions such as rain, dust, heat and cold. The resins that make up exterior paints also offer better adhesion to surfaces which means they will withstand high winds and heavy rains much better than interior paints.

Exterior paint will resist mold, mildew, fungi and bacteria growth on wooden fences and decks because it has wetter film properties which keep the surface dryer when exposed to moisture or humidity. This means it won’t peel or flake like an interior paint would. Exterior paints contain UV inhibitors as well as mildew inhibitors, fungicides and germicides which make them ideal for areas where there is increased humidity or moisture such as bedrooms, bathrooms, kitchens and basements.

Other factors worth considering before choosing exterior paint include; the condition of your siding, trimwork (if you have any), eaves and gutters as well as your roof type (should be metal for results that last longer). Before choosing exterior paint  consider the type of surface you have. If your fence or deck is covered in mold, mildew or algae then you will need an anti-mold, mildew and algae treatment before painting which will give the surface a clean slate to work with.

Exterior paints are available in gloss and semi-gloss formula to protect against cracking. They also look best when applied over light colored surfaces (you may need to do multiple coats if your house is a dark color). You should choose exterior paint that is made with heavy resins because they have more mildew resistance than paints with thinner resins which means less re-coating will be needed. Exterior paints can expand up to four times its original volume once it cures, so don’t forget to factor in the weather conditions into the equation as well before making a final decision on what’s right for you home.

Exterior paint may seem expensive but if you choose a good quality brand that is water resistant, mildew resistant, durable and ecofriendly then the money spent on this investment will be well worth it in the long run. As with any painted surface, frequent washing is highly recommended to prolong the life of your exterior paint job as harmful UV rays from the sun can damage it after time which will also decrease its durability.

Flat Paint or eggshell? Paint manufacturers have developed high-gloss paints that work very well for the interior walls of your home but now they come with a flat finish which makes them great for use on wooden decks and fences. Flat exterior paints are low odor and easy to clean so if you prefer a matte finish that is easy to maintain then this is the best choice for you.

Exterior primers are very important when it comes to painting your home’s wooden fences or decks because they protect from moisture and also from direct sunlight which can cause fading over time. These high-quality primers are not like the ones used in interior paint jobs and once applied, will need a couple of coats before another coat of topcoat exterior paint is applied afterwards. This helps avoid cracking that might occur as a result of incorrect application. Always choose an exterior primer that has been formulated specifically for wood fences and decks, otherwise you run the risk of damaging your fencing by using too many coats (more surface area = more chance of bubbling/peeling).

Exterior paints are easy to apply but they must be applied correctly otherwise it can ruin your expensive new deck or fence and turn into a big expense instead of a small one. All surfaces should be pressure washed first then primed (if required) before applying any kind of topcoat paint afterwards. This ensures that all loose debris and dirt particles are removed from the wood so that when it’s painted over, there won’t be any unsightly cracks in the paint.


Though it might seem insignificant when deciding where to use exterior paint, the consequences can be very real. If you put exterior paint on inside walls, you’re likely to experience chemical fumes in your house. When you apply interior paint to outside surfaces of your house, it will crack and chip away quickly and a short time.

Different paints are for different surfaces. For example, paint that is meant for outside is not the same as paint that can be used on inside walls. If you want to make sure the paint will work on both, you could use an indoor/outdoor paint.


Looking for a painting expert to help with your next project? We can help at Ethereal Painters. Fill out our FREE estimate form or give us a call at 604-505-2745 today.